In recent years, as recording media such as CDs (Compact Discs) are coming into wide use and various audio compression techniques are making advance, music data is digitalized to be processed in general. Furthermore, as selling commercial products using the Internet is becoming widespread, there is employed a method of selling music CDs and their audio data through the Internet. For example, there are provided a service of delivering a package of music CDs to an applicant's home when making an application of purchasing the package through a Web site of a CD shop, and a service of providing downloadable audio data of tunes by an album unit or by a tune unit from a fee-based music delivery site.
In case of purchasing music data through the Internet, application for purchase is possible after having an access to a CD shop site or a music delivery site, and carrying out retrieval using a desired tune name or artist name, and displaying a list  of music CDs or a list of tunes on a display and confirming the contents thereof. There are many services which allow experimentally listening to tunes displayed in a list before purchasing the tunes. In this case, a selling site prepares compressed data for part of tunes respectively in advance, and delivering the compressed data of the tunes in the streaming manner in answer to a request from the user. The user can reproduce and output thus delivered compressed data only once.
Furthermore, there is employed a method of displaying a list of tunes on a display of the user, and consecutively reproducing thus displayed respective tunes automatically. This function, which not only makes the user confirm the contents of the tunes before purchase but also brings about an effect of introducing the tunes to the user, is very important for promoting the selling.
As a conventional related art, there is employed a tune identification delivery system, to be explained hereinafter, in which a tune is easily specified using part fragment of the tune and the tune can be purchased after experimentally listening to the tune. In the system, firstly, music data is recorded to a cellular phone terminal using a microphone, and thus recorded music data is transmitted to the tune identification delivery system. Then, the tune identification delivery system retrieves data for experimental listening corresponding to the music data by employing matching, and transmits thus retrieved data to the cellular phone terminal. After experimentally listening to the data for experimental listening using the cellular phone terminal, the user can have an access to a music delivery system to purchase the music (for example, refer to Patent Document 1). 
Patent Document 1 (Japanese Patent Laid-Open Publication No. 2002-116768, paragraph numbers [0053] to [0072], FIG. 7).